In this video, NPR shows us how the speed of light was first estimated, and how you can do a similar measurement yourself–using those leftover marshmallow Easter peeps and a microwave.
Events
ALAN 2025 – Artificial Light At Night Conference 2025
Westport, Co. Mayo, Ireland
October 28 - 30, 2025
Archives
Categories
About
Launched in 2001, LightNOW covers the rapidly changing lighting world for lighting people. Check-in daily to see new posts by Editor David Shiller, Craig DiLouie, and other experts in the lighting field including consultants and lighting designers. Posts include news items to keep you up to date, short opinion pieces to invite you to consider another point of view, new products every Monday, and links to new research and tools to help you design with light. Also be sure to subscribe to the LightNOW newsletter (free), which is published every two weeks as a digest of articles on the site. We always welcome your feedback, so feel free to comment on any of the stories that appear here at LightNOW. If you are a manufacturer, LightNOW offers a low-cost ad vehicle to reach thousands of specifiers, contractors, reps, distributors, consultants, owners, and other stakeholders in the sales channel. For advertising inquiries, contact Suelynn Shiller. Thank you for visiting, and we hope you find LightNOW useful for your career in lighting
Lighting Solution Development
7889 River Hill Lane, Alexandria, PA 16611-2604
THE INFORMATION CONTAINED IN ALL ARTICLES PUBLISHED ON WWW.LIGHTNOWBLOG.COM HAS BEEN OBTAINED FROM SOURCES BELIEVED TO BE RELIABLE. DAMAGES ARISING FROM ERRORS, OMISSIONS, OR DAMAGES AS A RESULT OF THE USE OR MISUSE OF THE DATA OR INFORMATION CONTAINED AT WWW.LIGHTNOWBLOG.COM ARE NOT THE RESPONSIBILITY OF LIGHTING SOLUTION DEVELOPMENT, INTER.LIGHT, INC., ZING COMMUNICATIONS, INC., OR THEIR EMPLOYEES. ALL INFORMATION CONTAINED AT WWW.LIGHTNOWBLOG.COM IS PUBLISHED FOR PROFESSIONALS SEEKING INFORMATION ABOUT THE SUBJECTS CONTAINED THEREIN. IT IS NOT THE INTENT OF WWW.LIGHTNOWBLOG.COM TO PROVIDE PROFESSIONAL SERVICES SUCH AS DESIGN, ENGINEERING, OR CONSULTING. IF THESE SERVICES ARE SOUGHT, THEY SHOULD BE RENDERED BY PROPERLY TRAINED, REGISTERED, REGULATED AND INSURED PROFESSIONALS.